The active saturated iron-core superconductive fault current limiter(SISFCL)is a good choice to decrease fault current.This paper introduced the principles and impedance characteristic of the active SISFCL.Then,it sho...The active saturated iron-core superconductive fault current limiter(SISFCL)is a good choice to decrease fault current.This paper introduced the principles and impedance characteristic of the active SISFCL.Then,it shows the current-limiting effects of the SISFCL.Besides,the impact of the active SISFCL on the distance protection of the EHV transmission line is evaluated.Based on that,the coordination scheme of the distance protections is proposed.A 500 kV double-circuit transmission system with SISFCLs is simulated by Electro-Magnetic Transients Program including DC(EMTDC).Simulation tests demonstrate the correctness and validity of theoretical analyses.展开更多
In DC micro grids and networks,DC-DC power converters having a large number of semiconductor-based power electronic devices are usually adopted to interconnect the renewable sources and flexible loads.Most of the semi...In DC micro grids and networks,DC-DC power converters having a large number of semiconductor-based power electronic devices are usually adopted to interconnect the renewable sources and flexible loads.Most of the semiconductor-based devices suffer from poor fault withstanding abilities,but conventional power electronic protection schemes have the bottlenecks of the time-delay,self-malfunction and mis-judgement.This paper presents a novel solution using the superconducting fault current limiter(SFCL)to protect a power electronic device and extend the usage to a micro grid.This SFCL is actually a self-triggering,recoverable,and passive current limiter,which does not involve any additional circuit hardware and software.Experimental investigations and simulation analyses clarify the feasibility of using this superconductor-based protection scheme to implement the self-acting fail-safe protection of DC-DC converters.Further system-level simulations explore the SFCL to suppress the over-current and stabilize the bus voltage of a photovoltaic based DC micro grid,particularly facing millisecond-level transients and faults.Our experimental and theoretical investigations lay some technical bases to establish a superconductor-semiconductor-coupled interdisciplinary application from the view from the applied superconductivity,to power electronics,and to micro grids.展开更多
普通桥式超导故障限流器(Superconducting Fault Current Limiter,SFCL)只能限制故障短路电流的峰值,不能限制短路电流的稳态值。应用电力电子技术对桥式超导限流器的结构进行改进,能在保持原有桥式限流器优点的基础上,有效限制短路电...普通桥式超导故障限流器(Superconducting Fault Current Limiter,SFCL)只能限制故障短路电流的峰值,不能限制短路电流的稳态值。应用电力电子技术对桥式超导限流器的结构进行改进,能在保持原有桥式限流器优点的基础上,有效限制短路电流的稳态值。针对一种新型桥式SFCL,在分析其限流过程的基础上,利用PSCAD仿真系统分析发生三相短路故障时的限流情况,并对影响其限流效果的限流电阻、超导电感及电阻投切装置的响应时间3个主要参数进行了进一步的讨论。结果表明,该限流器在配电网中不仅能有效地限制短路故障电流,抑制母线电压跌落,而且不用更换现有的开关设备,具有较大的经济效益。展开更多
普通桥式超导故障限流器(Superconducting Fault Current Limiter,SFCL)只能限制故障短路电流的峰值,不能限制短路电流的稳态值。应用电力电子技术对桥式超导限流器的结构进行改进能在保持原有桥式限流器优点的基础上,有效限制短路电流...普通桥式超导故障限流器(Superconducting Fault Current Limiter,SFCL)只能限制故障短路电流的峰值,不能限制短路电流的稳态值。应用电力电子技术对桥式超导限流器的结构进行改进能在保持原有桥式限流器优点的基础上,有效限制短路电流的稳态值。针对现今的研究热点,着重介绍了全控桥型、电阻投切型、混合型、有源型等几种实用价值较高的桥式SFCL的工作原理及其特点,并对桥式超导限流器研究中存在的问题及其发展趋势做了说明。展开更多
高温超导限流器(SFCL)是一种限制电网短路电流的有效措施,500 k V SFCL设备研制已有较大发展,对500k V SFCL接入电网系统的工程方案进行了研究,首先介绍了SFCL的工作原理,结合220 k V和35 k V SFCL投入电网的运行情况分析了SFCL的故障类...高温超导限流器(SFCL)是一种限制电网短路电流的有效措施,500 k V SFCL设备研制已有较大发展,对500k V SFCL接入电网系统的工程方案进行了研究,首先介绍了SFCL的工作原理,结合220 k V和35 k V SFCL投入电网的运行情况分析了SFCL的故障类型,接着针对500 k V SFCL的设备特点和电网要求,提出了一种主接线方案,该方案具有可靠性高,运行灵活,施工方便等特点,并给出了2个适用于不同工程环境情况下的平面布置方案。展开更多
文摘The active saturated iron-core superconductive fault current limiter(SISFCL)is a good choice to decrease fault current.This paper introduced the principles and impedance characteristic of the active SISFCL.Then,it shows the current-limiting effects of the SISFCL.Besides,the impact of the active SISFCL on the distance protection of the EHV transmission line is evaluated.Based on that,the coordination scheme of the distance protections is proposed.A 500 kV double-circuit transmission system with SISFCLs is simulated by Electro-Magnetic Transients Program including DC(EMTDC).Simulation tests demonstrate the correctness and validity of theoretical analyses.
基金the National Natural Science Foundation of China[Grant No.51807128].
文摘In DC micro grids and networks,DC-DC power converters having a large number of semiconductor-based power electronic devices are usually adopted to interconnect the renewable sources and flexible loads.Most of the semiconductor-based devices suffer from poor fault withstanding abilities,but conventional power electronic protection schemes have the bottlenecks of the time-delay,self-malfunction and mis-judgement.This paper presents a novel solution using the superconducting fault current limiter(SFCL)to protect a power electronic device and extend the usage to a micro grid.This SFCL is actually a self-triggering,recoverable,and passive current limiter,which does not involve any additional circuit hardware and software.Experimental investigations and simulation analyses clarify the feasibility of using this superconductor-based protection scheme to implement the self-acting fail-safe protection of DC-DC converters.Further system-level simulations explore the SFCL to suppress the over-current and stabilize the bus voltage of a photovoltaic based DC micro grid,particularly facing millisecond-level transients and faults.Our experimental and theoretical investigations lay some technical bases to establish a superconductor-semiconductor-coupled interdisciplinary application from the view from the applied superconductivity,to power electronics,and to micro grids.
文摘普通桥式超导故障限流器(Superconducting Fault Current Limiter,SFCL)只能限制故障短路电流的峰值,不能限制短路电流的稳态值。应用电力电子技术对桥式超导限流器的结构进行改进,能在保持原有桥式限流器优点的基础上,有效限制短路电流的稳态值。针对一种新型桥式SFCL,在分析其限流过程的基础上,利用PSCAD仿真系统分析发生三相短路故障时的限流情况,并对影响其限流效果的限流电阻、超导电感及电阻投切装置的响应时间3个主要参数进行了进一步的讨论。结果表明,该限流器在配电网中不仅能有效地限制短路故障电流,抑制母线电压跌落,而且不用更换现有的开关设备,具有较大的经济效益。
文摘普通桥式超导故障限流器(Superconducting Fault Current Limiter,SFCL)只能限制故障短路电流的峰值,不能限制短路电流的稳态值。应用电力电子技术对桥式超导限流器的结构进行改进能在保持原有桥式限流器优点的基础上,有效限制短路电流的稳态值。针对现今的研究热点,着重介绍了全控桥型、电阻投切型、混合型、有源型等几种实用价值较高的桥式SFCL的工作原理及其特点,并对桥式超导限流器研究中存在的问题及其发展趋势做了说明。
文摘高温超导限流器(SFCL)是一种限制电网短路电流的有效措施,500 k V SFCL设备研制已有较大发展,对500k V SFCL接入电网系统的工程方案进行了研究,首先介绍了SFCL的工作原理,结合220 k V和35 k V SFCL投入电网的运行情况分析了SFCL的故障类型,接着针对500 k V SFCL的设备特点和电网要求,提出了一种主接线方案,该方案具有可靠性高,运行灵活,施工方便等特点,并给出了2个适用于不同工程环境情况下的平面布置方案。
